The invention relates to a method for the camera-assisted detection of the radiation intensity of a chemical reaction product, in particular a gaseous reaction product, where an emission rate for the radiation intensity of the reaction product is generated from the difference of a band radiation value of the reaction product and a temperature radiation value arrived by pyrometry.
From the German patent publication DE 197 10 206 A1, a method and a device are known for a combustion analysis as well as flame monitoring in a combustion chamber. In order to rapidly detect the temperature distribution, the concentration distribution of reaction products as a result of the combustion process, as well as the parameters of the flame, a picture is taken of the flame to determine from the locally defined intensities of the picture, a spatial distribution of the combustion process characterizing parameters, at least for a predetermined spectral range. An optical system of the device comprises a lens for detecting the flame, as well as three downstream beam splitters. The bundled beams that are detected by the lens are supplied to at least four spectral ranges by means of the beam splitters and then submitted to a CCD-image sensor.
Finally, the invention refers to a device corresponding to the method. The device includes a processing unit with means for generating an emission rate for the radiation intensity of the reaction product from the difference of a band radiation value of the reaction product and a temperature radiation value of the reaction product generated by pyrometric means.
From European Patent application EP 1 091 175 B1, a method as well as a corresponding device are known for determining the excess air in a combustion process, where the formation rates of the reaction products, CN and CO from the combustion reaction are determined. Subsequently, the ratio of the determined formation rates is expressed as a value represented by the excess of air. For detecting the beam intensities at least four special cameras are contemplated.
From the European patent application EP 0 469 258 A1, a device is known for the three-dimensional image of the temperature of a flame, specifically, for the image of several flames of a burner in a boiler, such as for example in a power station. The device includes a TV-color camera for taking a picture of the flame to be imaged, wherein the TV-color camera is configured for the output of respective color signals. The device also includes a control unit having functional units that are suitable to produce from the image taken a vectorial temperature distribution by means of a two-color pyrometry. In that embodiment, it is recommended to utilize the red and green signal of the TV-color camera for the two-color pyrometry. It is specifically recommended, not to utilize the blue signal of the TV-color camera due to its low brightness and its drawback due to chemical phenomena.
In the presently known methods and devices, the drawback is that the camera systems must be oriented in possibly pixel-exact manner relative to each other in order to avoid reproduction errors between the spectrally different evaluation ranges. Thereby, additional thermal expansion effects as well as mechanical vibration that impact the optical system must be taken into account. Accordingly, each optical system must be built for a robust and stable condition. As a result, the systems are very expensive.
A further disadvantage is the time consuming mechanical adjustment of such an optical system. In addition, such systems are comparatively maintenance intensive.
A further big disadvantage is the necessary temporal synchronization between the cameras in order to realize a temporal coordination of each of the brightness signals of the cameras for the different split wave lengths ranges. Thus, the control-technical expenditure is correspondingly high.
Starting from the prior art as discussed, it is an object of the invention, to provide a method for camera assisted detection that is less costly.
It is a further object of the invention to provide suitable applications for the method according to the present invention.
Finally, it is an object of the invention to provide a corresponding device, which is less complex and at the same time more reliable.